RESUMO
A series of pegylated cis-A2B2- or A3B-type ZnPcs, substituted on the α-positions with tri(ethylene glycol) and hydroxyl groups, were synthesized from a new bis-phthalonitrile. A clamshell-type bis-phthalocyanine was also obtained as a byproduct. The hydroxyl group of one ZnPc was alkylated with 3-dimethylaminopropyl chloride to afford a pegylated ZnPc functionalized with an amine group. All mononuclear ZnPcs were soluble in polar organic solvents, showed intense Q absorptions in DMF, and had fluorescence quantum yields in the range 0.10-0.23. The clamshell-type bis-phthalocyanine adopts mainly open shell conformations in DMF, and closed clamshell conformations in chloroform. All ZnPcs were highly phototoxic to human carcinoma HEp2 cells, particularly the amino-ZnPc mainly protonated under physiological conditions, which showed the highest phototoxicity (IC50 = 0.5 µM at 1.5 J/cm2) and dark cytotoxicity (IC50 = 22 µM), in part due to its high cellular uptake. The ZnPcs localized in multiple organelles, including mitochondria, lysosomes, Golgi and ER.
RESUMO
Spherical iron-carbon nanocomposites were developed through a facile aerosol-based process with sucrose and iron chloride as starting materials. These composites exhibit multiple functionalities relevant to the in situ remediation of chlorinated hydrocarbons such as trichloroethylene (TCE). The distribution and immobilization of iron nanoparticles on the surface of carbon spheres prevents zerovalent nanoiron aggregation with maintenance of reactivity. The aerosol-based carbon microspheres allow adsorption of TCE, thus removing dissolved TCE rapidly and facilitating reaction by increasing the local concentration of TCE in the vicinity of iron nanoparticles. The strongly adsorptive property of the composites may also prevent release of any toxic chlorinated intermediate products. The composite particles are in the optimal range for transport through groundwater saturated sediments. Furthermore, those iron-carbon composites can be designed at low cost, the process is amenable to scale-up for in situ application, and the materials are intrinsically benign to the environment.